.editor {
  display: flex;
}

.line-numbers {
  width: 20px;
  text-align: right;
  padding-right: 10px;
  color: #506882;
  font-family: monospace;
  font-size: 14px;
  line-height: 20px;
}

.line-numbers span {
  counter-increment: linenumber;
}

.line-numbers span::before {
  content: counter(linenumber);
  display: block;
}
